Almonte, who prosecuted cases for the U.S. Attorney's Office in San Antonio, said the fraud Mello is accused of committing appeared to be fairly simple.

"I think sometimes you think the monetary amount — $100 million or many millions — and you assume it was some sort of complex scheme," Almonte said. "But you can boil it down to an employee embezzling from their employer. It’s nothing super complex or discreet on her part.

"In some fraud instances, they at least take steps to make sure to hide their fraud," he added. "There was no apparent attempt to hide what she was doing with the money after the fact."

Like Almonte, Mike Lemoine, who retired from the IRS' criminal investigation division, one of the agencies investigating Mello, noted the alleged theft was "definitely brazen."

Lemoine investigated cases like Mello's, though none of them involved such a staggering amount of money stolen so quickly. He said government officials sometimes rely on the honor system because they don't have the controls in place to prevent fraud. 

That's often because of inadequate funding or, in the military's case, staff turnover, said two agents who currently investigate military fraud crimes. They asked not to be identified because they are not authorized to speak with the media.

"They're relying on the good faith standard that the government sometimes employs to conduct business, with the understanding that their employee is not going to rip them off," Lemoine said.

But something as simple as an employee setting up a limited liability company, such as CHYLD, should raise a red flag. Investigators can view LLCs, which protect owners from personal responsibility for the company's debts and other liabilities, as a "a type of concealment" for fraud, Lemoine said.

"We used to call it, 'Hiding in the open,'" he added.

Some civil servants, depending on their pay grade or work environment, are required to disclose any businesses they own or have invested in. They also go through ethical training, where they are reminded of the required disclosures. It was not clear if Mello was required to do so.

Mello, who was indicted Dec. 5, turned herself in Thursday at the federal courthouse in San Antonio. She made her first court appearance and was not deemed a flight risk and released on personal recognizance, without making any public comments about her case.

Her lawyer, Albert Flores, limited his comment because he said he hadn't seen the investigation reports and other information that prosecutor relied on in seeking the indictment against Mello. 

"We don't have any information from the government yet," Flores said. "I imagine, based on the nature of the case, that it will be a while and be extensive."

Mello, who is no longer an Army employee, is expected to plead not guilty at her arraignment, which is set for next Thursday.

Her company had been in operation for six years when criminal investigators with the IRS and the Army zeroed in on it, culminating in her indictment.

Lap of luxury

Last week, federal investigators filed paperwork saying they want to keep the $140,000 Mercedes-Benz GLS 63 AMG they seized from Mello.

They want to hang on to some other items, too — a 2018 Mercedes-Benz GTS AMG, which goes for about $100,000; a 2018 Maserati Grand Turismo, worth about $130,000; and 75 other high-end cars, SUVs, trucks and motorcycles owned by or linked to Mello.

In fact, the filing said, the federal government intends to keep all the luxurious accessories, real estate, jewelry, $18 million in cash, and vintage cars and motorcycles seized from or connected to Mello.

The document, known as a “bill of particulars for forfeiture of property,” puts Mello on notice about what items federal agents are targeting for seizure as fruits of her alleged crimes.

“That bill of particulars lists and details the property the government might keep,” said one federal agent, who requested anonymity because he works undercover. “When you go and seize stuff, you don’t know if all of it was acquired as a result of the crimes they are charged with. It's like an inventory, and what it does is let the defendant know that the government is going to seek forfeiture.”

Generally, forfeited property, such as cars, houses, jewelry and real estate, is sold at auction to compensate victims and pay some of the costs for investigating and prosecuting the criminal activity.

Mello's purchases included what amounted to a collector's wish list of motorcycles, including Harley-Davidson, Indian, Triumph, BMW and Ducati bikes, some of them extremely rare and dating to the early 1900s. Also on the list are sought-after classic or muscle cars including a 1966 Ford Mustang, a 1967 Camaro SS and a 1954 Chevrolet Corvette.

In addition to the 78 vehicles, authorities listed 31 properties in Texas and five other states, including posh estates and large tracts of undeveloped land, that agents believe Mello paid for with stolen funds. Some of the property is in Horseshoe Bay, northwest of Austin, and some is near the village of Cloudcroft in the rugged mountains of southeastern New Mexico.